Santa Clara County, California. Santa Clara County, California, officially the County of Santa Clara, is a county in the U.S. state of California. As of the 2010 census, the population was 1,781,642.
The Argyle Diamond Mine is the worldâs largest diamond mining operation by volume, although not necessarily by value. Located in Australia, this mine covers 110 acres, and reaches down underground about 1,900 feet at its deepest part.
Kimberley Mine (The Big Hole) Kimberley, South Africa. At a depth of more than 700 feet and a width of 1,519 feet, itâs hard to believe The Big Hole started as a hill. More than 6,000 pounds of diamonds were unearthed from this site, and at one point, up to 50,000 miners had their picks in the earth.